DC servo-motors and controllers have a wide variety of application in industry. This combination is commonly used to accurately control the position of an output such as the table on a machine tool or the surface of a fin on a missile. Other common applications include the control of the speed of an output such as a fan or a flow metering pump. The physics and engineering of the basic motor and controller concepts are well known.
As technology and industry progress, the need for greater precision and versatility at lower cost has risen. New controller and sensor technology are enabling the design of new and innovative designs to meet these objectives.